This invention relates to the production of flame-retardant polyurethane products by an improved process which utilizes amino salts of phosphorus acids as the flame-retardant and in production of foams a hydrated amino salts of phosphorus acids are used. The hydrated flame-retardant products also function as the blowing agent because the water is slowly released thereby greatly reducing the need for halogenated blowing agents.
The amino salts of phosphorus acids are produced by mixing and reacting an amino compound and a phosphorus acid type compound. In the process of this invention, low-cost and readily available compounds are utilized in the production of the flame-retardant compounds. Many types of flame-retardant chemicals have been used in polyurethane production but there is still a need for a flame-retardant which can be used, especially in flexible polyurethane foams, that is predominantly inorganic, that is relatively inexpensive, that will act as the blowing agent, that prevents the foam from burning and reduce smoke production. The flame-retardants of this invention will fill this need.